Pipe organ system



Sept 4, 1956 J. H. HAMMOND, JR 2,761,343

PIPE ORGAN SYSTEM 4 Shee'cs-SheetV 1 Filed Feb. ll, 1953 attorney PIPE ORGAN SYSTEM 4 Sheets-Sheet 2 Filed Feb. ll, 1953 linvenfor uol-m HAY's HAMMOND, JR.

NON wom Q PIPE ORGAN SYSTEM Filed Feb. 11, 1953 4 Sheets-Sheet 3 ZIB MOTION 0F SWELL. PEDAL Suventor JOHN HA'YS HAMMONDJR.

Gttorneg J. H. HAMMOND, JR 2,761,343

Sept. 4, 1956 PIPE ORGAN SYSTEM Filed Feb. ll, 1953 4 Sheets-Sheet 4 AUnited States Patent O PIPE ORGAN SYSTEM John Hays Hammond, Jr., Gloucester, Mass.

Application February 1`1, 1953, Serial No. 336,275

3 Claims. (Cl. 84--1.04)

This invention relates to pipe organs and has for an object to improve the tonal qualities of the music propagated from a pipe organ into an auditorium.

This application is a continuation-in-part of my copending applications Serial No. 260,192 filed December 6, 1951, for Pipe Organ System and Serial No. 263,771 filed December 28, 1951, for Pipe Organ System (now abandoned).

Polyphonic music depends upon a contrast of different tonalities. This is accomplished by differences of tone color or differences of intensity. The beauty of orchestration lies in the ever changing movement of tonal timbre, one timbre for a moment coming to the foreground and dominating the ensemble only to give way to another timbre.

The present invention provides a method for emphasizing the contrast in the different tonal sections, thus producing a sharper polyphonic effect. The instrument develops clarity of expression and has the clear cut quality of the piano and lacks the characteristic muddiness of many organs.

Another feature is the ability to produce in organ music far greater changes in dynamics than is now possible with the ordinary swell shades. This permits greater dramatic emphasis and adds to the flexibility of control by the organist.

Another feature resides in transferring into the auditorium the delicate harmonics which are present in the organ chambers and which are often lost in transmission.

The present invention permits the use of delicate stops against larger ensembles, as these stops can be expanded in their volume while maintaining their color. Also greater staccato effects are achieved due to a factor of speed in the electrical transmission of the sound from the organ chamber to the auditorium.

Pipe organ chambers are usually closed except for swell shutters which are under the control of the organist and are arranged to be opened progressively for increasing the volume of sound transmitted from the chamber to the auditorium. However, such shutters are most effective during the first third of their movement and thereafter have but slight effect on the volume. Hence the control is non-linear and restricted to only a portion of the total pedal movement.

I have found that the control can be enhanced and made effective in a linear or even an expanded relationship to the pedal motion by providing an electrical transmission system including a microphone in or near the chamber and a speaker in the auditorium near the organ. Such system supplements the mechanical control of the shutters. The transmission efficiency of the electrical system is arranged to be varied by the swell shutter motion to produce the desired volume expansion. The electrical system may become effective after the shutters have been opened to their position of maximum differential control (about one-third of their movement) and may be arranged to increase the volume with further shutter movement, or if desired the electrical systems can be operated simultaneously with the swell shutters throughout their range of movement. In either case the characteristics may be determined by a suitable control potentiometer or the like actuated by the swell pedal and designed to have a predetermined characteristic which may be linear or non-linear as desired.

A feature of the present invention is the control of the swell motors and of the electrical pick-up system by successive positions of the swell pedals.

Another feature is the provision of selective controls for the different organ chambers and a master control for controlling a group of chambers in unison.

Another feature resides in the introduction of artificial reverberations into the pick-up system so that the reproduced sound is caused to simulate the natural organ tones.

The invention also consists in certain new and original features of construction and combinations of parts hereinafter set forth and claimed.

The nature of the invention, as to its objects and advantages, the mode of its operation and the manner of its organization, may be better understood by referring to the following description, taken in connection with the accompanying drawings forming a part thereof, in which:

Fig. l is a schematic diagram of the invention as applied to a pipe organ having a plurality of organ chambers;

Fig. 2 is a schematic wiring diagram of the pedal control mechanism;

Fig. 3 is a set of curves representing the relationship between the pedal motion and the audible sound intensity; and

Fig. 4 is a detail view of an embodiment wherein the shutter actuates the volume control mechanism.

Like reference characters denote like parts in the several figures of the drawing.

In the following description parts will be identified by specific names for convenience, but they are intended to be generic in their application to similar parts.

Referring to the accompanying drawings and more particularly to Fig. 1 a plurality of'organ chambers are indicated at 11 and 12. Mounted in these chambers are a plurality of organ chests 13 and 14, which, for example may be the Solo and Great chests. On these chests are mounted sets of pipes indicated at 15 and 16 respectively. The organ chambers are provided with sets of swell shutters 18 and 19, which are operated by swell motors 21 and 22, in the usual manner, by means of shafts 23 and 24.

Mounted in the organ chambers 11 and 12 are microphones 25 and 26 respectively which are connected through preamplifiers 27 and 28 and transformers 29 and 3), to potentiometers 31 and 32 respectively. The movable contacts 33 and 34 of these potentiometers are mounted on blocks of insulation 3S and 36, which are secured to the cores 37 and 3S of solenoids 39 and 40. Surrounding the cores 37 and 38 are compression springs 42 and 43 which tend to hold the contacts 33 and 34 in the positions shown.

The contacts 33 and 34 fare connected by conductors 46 and 47 to amplifiers 48 and 49 respectively, the output circuits of which are connected by conductors 51 and 52 to output mixer circuits 53 and 54. The output circuits of the mixers 53 `and 54 are both connected by conductors 55' and 56 to =a low power amplifier 57 the output circuit of which is 'connected through a reverberation device 58 to the input circuit of a power `amplifier 61 the output circuit of which is connected to a plurality of loud speakers 62.

The reverberation device 5S may be of any well known and standard construction, such for example, as that described in an article entitled Synthetic reverberations by P. C. Goldm'ark and P. S. Hendricks in the Proceedings of the institute of Radio Engineers, December 1939, vol. 27, No. l2, pp. 747-752. The article describes a system in which sound is recorded on a rotating member and picked up from the member after a predetermined period of delay. The picked up delayed sound and the original sound are mixed as desired to produce reverberation effects. Referring to Fig. 8 of this article the output circuit of amplifier 57 is connected to the input circuit shown in this figure and the output circuit of the reverberation device is connected to the input circuit of the power amplifier 61. Any suitable means may be ernployed for bypassing the reverberation device 58, so that when it -is not desired to use this device it may be eliminated from the circuits.

For controlling the swell shutters and the amplification system a pedal control mechanism 65 is provided. Mounted on the front of this mechanism are three pedals 66, 67 and 68. The pedals 66 and 67 yare connected to control the swells and yamplification of the Solo and Great organs in chambers 11 and 12 respectively while the pedal 68 is the unison pedal which is connected to control both organs simultaneously as shown in detail in Fig. 2.

Referring to Fig. 2 for a more detailed construction of the pedal control mechanism 65, the three pedals 66, 67 and 68 are rotatably mounted on brackets 71, 72 Iand 73, respectively which are secured to the frame 74 of the control mechanism 65. The upper end of the pedal 66 is pivotally connected by a link 75 to 'a bar of insulating material 76, which is slidably mounted in the frame 74 yand which carries on one face a contact strip 77. Resting on the bar 76 are four contact fingers 78, 79, S and 81, which are connected by conductors 82, 83, 84 and 85 to contact plates 86, 87, 88 and 89 respectively, mounted on a base 91a of insulating material. Mounted on the end of the bar 76 is `a contact 91 which slides on resistor 92 forming a rheostat. The contact 91 'and resistor 92 are connected by conductors 93 and 94 to contact plates 95 and 96 which are mounted on the base 91a.

A roll 97 is rotatably mounted in two brackets 98, which are fastened to the base 91. Secured to the roll 97 is an `armature of magnetic material 99 to one end of which is secured a spring 101. An electromagnet 102 is mounted on the base 91 and is located adjacent to the other end of armature 99 in a position to cause rotation of the armature and roll when energized. Secured to the roll 97 are six contact fingers 103, 104, 105, 106, 107 and 108 adapted to engage contact plates 86, 87, 88, S9, 95 and 96 respectively. The mechanism just described is known las the solo pedal control mechanism 111.

An identical mechanism known as the Great pedal control mechanism 112 is operated by the pedal 67 and the parts thereof are given the same reference numbers as similar parts of the Solo control mechanism 111.

The upper end of pedal 68 is pivotally connected by Ia link 114 to a bar of insulating material 115, which is slidably mounted in the frame 74 and which carries on one face a contact strip 116. Resting on the bar 116 are four contact fingers 117, 118, 119 and 120 which are connected by conductors 121, 122, 123 land 124 to contact plates 125, 126, 127 and 128 respectively mounted on a base 129 of insulating material. Mounted on the end of the bar 115 is a contact 131 which slides on a resistor 132 to form a rheostat. The contact 131 and resistor 132 are connected by conductors 133 and 134 to contact plates 135 'and 136 respectively which are mounted on the base 129.

Two rolls 138 and 139 are rotatably mounted in two sets of brackets 141 and 142, which are fastened to the base 129. Secured to the rolls 138 and 139 are armatures 143 and 144 made of magnetic material to the ends of which are secured springs 145 and 146 respectively. Electromagnets 147 and 148 are mounted on the base 129 'and Iare located adjacent to the other ends of the armatures 143 and 144 in a position to cause rotation of the rolls 138 and 139 when energized. Secured to the roll 138 are six contact fingers 151 to 156 adapted to engage contact plates 136, 135, 128, 127 and 126, 125 respectively when the rolls 138 and 139 are rotated by energization of magnets 147 and 148. Secured to the roll 139 `are .six contact fingers 15 7 to 162 also adapted to engage contact plates 136, 135, 128, 127, 126 and 125 respectively. The mechanism just described is known as the unison pedal control mechanism 163.

Mounted on the bar is a bracket 165 of insulating material which carries a contact finger 166, which in suitable positions engages one or the other of two contact bars 167 and 168. The contact linger 166 is connected through a low voltage supply 171 and ya switch 172 to one side of the windings of the electromagnets 102, 147 and 148. The other sides of the electromagnets 102 are connected to the contact bar 167 and the other sides of the windings of the electromagnets 147 and 148 4are connected to the Contact bar 168.

One side of the winding of the solenoid 39 (Fig. l) is connected by a conductor 181 to the Contact 152 (Fig. 2) and by branch conductor 182 to Contact 107 of pedal mechanism 111. One side of the winding of solenoid 40 (Fig. l) is connected by a conductor 183 to contact 158 and by branch conductor 184 to contact 107 of pedal control mechanism 112. The other sides of the windings of the solenoids 39 and 40 are connected by a conductor 185 to one side of a low voltage supply 186 the other side of which is connected by a conductor 187 to contact 157 and by branch conductors 188, 189 `and 190 to contact 151 and the contacts 108 of the two pedal mechanisms 111 and 112.

The contacts 153, 154 and 155 on roll 138 are connected by conductors 191, 192 `and 193 to the operating mechanism of the swell motor 21 (Fig. 1) which is of standard and well known construction. The return from this motor is connected by a conductor 194 to one side of 'a low voltage supply 195 the other side of which is connected by a conductor 196 to contact 162 and by branch conductors 197, 198 and 199 to contact 156 and contacts 103 of the two pedal mechanisms 111 and 112. The contacts 106, 105 and 104 of pedal mechanism 111 are connected by branch conductors 201, 202 and 203 to the conductors 191, 192 and 193 respectively.

The contacts 159 and 160, 161 on roll 139 are connected by conductors 205, 206 and 207 to the operating mechanism of the swell motor 22 (Fig. l). The return from this motor is connected by conductor 194 and branch conductor 208 to contact 160. The contacts 106,

105 and 104 of pedal mechanism 112 are connected by branch conductors 209, 210 and 2.1.1 to conductors 205, 206 and 207 respectively.

Operation In the operation of this invention the switch 172 is closed thus completing a circuit from the low voltage source 171, through contact finger 166, contact 167 and .the electromagnets 102 of the two pedal mechanisms 111 and 112. This energizes the magnets 102 causing the armatures 99 to be drawn down against the magnets. This rotates both rolls 97 in a clockwise direction causing contacts 103-108 to engage plates 86, 87, 88, 89, 95 and 96 respectively. If the Solo pedal 66 is now rotated in a counter-clockwise direction the bar 76 will Lbe moved to the left causing contact strip 77 to engage contact 79, which will complete a circuit from the low voltage source through conductors 196, 198, contact 103, plate 86, conductor 82, contact 78, strip 77, contact 79, conductor S3, plate 87, Contact 104, conductors 203 and 193, swell motor 21 and return 194 to source 195. This will operate the first step of swell motor 21 in a well known manner to open the swells 18 a small amount. As the pedal 66 is depressed further the strip 77 will successively engage contacts 80 and 81, which afferma will operate the second and third steps of swell motor 21 to open the swells 18 to about one-third the full amount. Any further depression of the pedal 66 will not affect the position of the swells, but will leave them open this amount.

When the roll 97 was rotated into position to close a circuit from the low voltage source 186 through conduc- -tors 187 and 189, contact 108, plate 96, conductor 94, resistor 92, contact 91, conductor 93, plate 95, contact 107, conductors 182, 181, solenoid 39 and conductor 185 back to source 186. As the full amount of resistance 92 was in the circuit only a small current flowed through the winding of solenoid 39, which was insufficient to retract the core 37 against the action of spring 42. As the rod 76 is moved to the left the contact 91 slowly passes over the resistor 92 gradually cutting down the resistance in the circuit, so that the current passing through the solenoid 39 is sufiicient to retract the core 37, which causes the contact 33 to gradually move over the potentiometer 31.

AThis results in transferring an increased amount of energy from the microphone 25 through the preamplifier 27 to the amplifier 48 where it is amplified and fed to the mixer 53. From here the energy passes to amplifier 57, where it is further amplified and fed through the reverberation device 58 to the power amplifier 61. Here the energy is still further amplified and fed to the loud speakers 62 to reproduce the music from the organ pipes in chamber 11. The reverberation device 58 adds artificial reverberation to the music produced by the loud speakers 62 in a manner described in connection with the article on Synthetic reverberations previously referred to. This produces an effect similar to that produced by organ music in a large auditorium or cathedral. As previously mentioned the reverberation device 58 may be eliminated from the circuit so that the music from the organ may be reproduced in the usual manner.

It is thus seen that as the pedal 66 is depressed during the first third of its motion the swells 18 will open to about one-third their full amount after which they will remain stationary and the organ music will be picked up by the microphone, amplified and reproduced by the loud speakers.

In Fig. 3 the curve 215 represents the sound passing through the swell shutters, that portion depicted by the curved line 216 being produced while the swells are opening during the first third of the pedal motion and that portion depicted by the straight line 217 being produced while the swells remain in a fixed position during the last two-thirds of the pedal motion. The increase of the sound intensity due to amplification is represented by the line 218, so that the line 216, 218 depicts the total sound which would be heard by a listener. In these curves the abscissae represent pedal motion and the ordinates audible sound intensity. In this way the large mechanical inertia of the swells is held to a minimum, while the electrical amplification may increase the total volume of sound produced to several times that possible by the use of the organ pipes alone.

In a similar manner when the Great pedal 67 is depressed the swells 19 of the Great organ chamber 12 will be opened about one-third after which the music picked up by microphone 26 will be amplified and reproduced in loud speakers 62 in a` manner similar to that already described.

When the pedals 66 and 67 are rotated in a clockwise direction the reverse action takes place as the bar 76 is moved to the right and the contact 91 moves to the right across resistor 92, thus decreasing the current through solenoids 39 and 40 causing the contacts 33 and 34 to move down, which decreases the amount of energy fed to the amplifiers and thus decreases the sound produced by the loud speakers 62. As the bars 76 con tinue their motion to the right the circuits through the contacts 81, 80 and 79 will be successively broken causing the swells 18 and 19 to be gradually closed.

As long as the unison pedal 68 is in the position shown the Solo and Great pedals 66 and 67 will control the swells 18 and 19 and the ampliers 48 and 49. When, however, it is desired to operate the swells and amplifiers in unison the unison pedal 68 is depressed which by means of the link 114 causes the bar 115 to be moved to the left. This will cause the contact 166 to move out of contact with bar 167 and into contact with bar 168. This will break the circuit through the magnets 102 of pedal mechanisms 111 and 112 allowing the armatures 99 together with rolls 97 to be restored to their open contact positions runder the action of springs 101, thus breaking all the circuits from the swell motors 21 and 22 and solenoids '39 and 40 to the pedal mechanisms 111 and 112. When the contact 166 engages the bar 168 a circuit will be closed from low voltage source 171 through magnets 147 and 148. When these magnets are energized the armatures 143 and 144 together with the rolls 138 and 139 will be rotated in a clockwise direction causing the contacts carried by the rolls 138 and 139 to engage the corresponding contact platos beneath them.

As the bar 115 moves to the left the strip 116 will successively engage the contacts 118, 119 and 120 thus closing the circuits through both swell motors 21 and 22 which will cause a simultaneous opening of the swells 18 and 19. As the bar 115 continues to move to the left the contact 131 will move over the resistor 132 causing a gradual increase of current through solenoids 39 and 40, which, as previously described, causes an increase of amplification by amplifiers 48 and 49. The output energy from these amplifiers is fed through mixers 53 and 54 to the amplifier 57, reverberation device 58 and power amplifier 61 after which it passes to the loud speakers 62, when it is reproduced as music.

It is thus seen that when the unison pedal is depressed that the Solo and Great pedals are made inoperative and that the unison pedal takes over control of all the swells and amplifiers and operates them in unison. When the unison pedal is returned to its initial position the circuits through the magnets 147 and 148 are broken making the unison mechanism 163 inoperative and the circuits to the magnets 102 are closed making the Solo and Great pedal mechanisms operative.

As indicated by the curve 215 the intensity of sound emitted through the swell shutters rises very rapidly during the first third of their motion. In order to make this curve more linear a variable speed mechanism may be introduced between the swell motor 21 and the shaft 23. This mechanism is shown in Fig. 4 and consists of a bell crank 220 pivoted at 221 to a bracket 222, which is secured to the frame 223 of the swell shutters 19. One arm of the bell crank 220 is pivotally connected by a link 224 to the operating shaft 226 of the swell motor 21. The other arm of the bell crank 220 is pivotally connected by a link 227 to the shaft 23 for operating the swells 19. Secured to the shaft 23 is a bracket 228 which is pivotally connected by link 229 to arm 230 of a volume control device 231 shown in the form of a tapered potentiometer which comprises an arm 232 moving on a series of contacts 233 to 238 between which are connected resistors 240 to 244 of progressively increasing resistance values. Thus resistor 240 may be of substantially zero value, so that the movement of the arm 232 produces no effect until contact 234 is reached. The width of the contact arm 232 is such that it is always in engagement with at least one of the contact buttons 233 to 238. This potentiometer may replace the potentiometers 31 and 32 of Fig. l when a variable volume control is required. This arrangement serves to increase the volume of the loud speakers in a non-linear or increasing function of the actuating movement.

ln the operation of this form of the invention the swell motor 21 is operated in the usual manner by the swell pedal at the console. When this pedal is depressed at a uniform rate the operating shaft 23 will move down at a variable rate, moving very slowly at first and then increasing in speed as the shutters open wider. In this way, the shutters 19 will open very gradually at first and then rapidly at the end of their motion, thus compensating, to some extent, for the effect of Webers law, which, as previously mentioned, would normally cause a rapid increase of audible sound intensity, which tapers off as the shutters open more fully.

The control of the volume directly from the swell shutters is advantageous on large organs when there may be an appreciable lag between pedal movement and shutter movement, as it ensures proper time sequence of build up of loud speaker volume and volume transmitted through the shutter openings.

The volume expansion produced by the non-linear potentiometer may be so combined with the shutter movement as to produce a substantially linear relationship between pedal movement and total volume.

Although only a few of the various forms in which this invention may be embodied have been shown herein, it is to be understood that the invention is not limited to any specic construction but might be embodied in various forms without departing from the spirit of the invention.

What is claimed is:

1. In a pipe organ having a bank of pipes and a wind chest enclosed in a swell chamber having a plurality of movable swell shutters by which the volume of sound transferred from the swell chamber is varied, a microphone disposed in sound pick-up relationship with respect to said swell chamber, a loud speaker disposed outside of said swell chamber, an electrical transmission channel connecting said microphone to said loud speaker, a volume control element in said channel adapted to control the transmission characteristics thereof, a swell pedal and means controlled by said pedal to actuate said swell shutters and said volume control element in sequence to cause the loud speaker to augment the variations in sound produced by said swell shutters.

2. in a system according to claim l, means connected to open said shutters successively.

3. A system according to claim 1 in which the pedal is connected to cause the increment of movement of said shutters for equal pedal movements to increase with shutter opening.

References Cited in the file of this patent UNITED STATES PATENTS 1,814,472 Hammond July 14, 1931 2,093,223 Yamashita Sept. 14, 1937 2,107,804 Raux et al. Feb. 8, 1938 2,199,702 Hammond May 7, 1940 2,431,962 Rettinger Dec. 2, 1947 2,441,425 Lawrence May 11, 1948 2,566,599 Chase Sept. 4, 1951 2,578,541 Hammond Dec. 11, 1951 

